Fried Model G/3 loudspeaker Manufacturer's Comment, Letters

Manufacturer's Comment

Editor: I was upset to learn that Dick Olsher regards our G/3 as a "lowly bass reflex." The "Line Tunnel" principle is something we developed years back as a next-best approximation to the virtues of true transmission lines. It does flatten impedance, giving one peak only, and in addition does contribute an additional source of low frequency information.

Some reviewers have called this a cross between air-suspension and bass reflex; others have called it any number of things. What it should be called is a Line Tunnel", or "Flow Resistance Loading system."Irving M Fried, Philadelphia, PA

A Letter in response appeared in January 1987 (Vol.10 No.1):

Unfair on Fried?

Editor: Dick Olsher's attacks on Mr. Fried's name and on Philadelphia in his review of the Fried G/3 loudspeaker (Vol.9 No.7) were totally irrelevant, inexcusable, and had no business being printed. I didn't know Stereophile was in competition with the supermarket tabloids. In addition, he claims that the measured bass response of the G/3 is only flat to 50Hz, and 9dB down at 31.5Hz.

He can't be serious!

A line-tunnel enclosurewhich is not a "lowly" bass reflex, as described by DOrolls off at 6dB/octave. It is impossible, therefore, for it to be down 9dB at 31.5Hz. The G/3 is flat to 25Hz.

Fried speakers are synonymous with excellent bass. I quote from JGH's Summer CES report on the G/3 in Vol.9 No.5: "There are two things I expect from Bud Fried's larger loudspeakers: unsurpassed reproduction of massed violin sound, and excellent bass. I was not disappointed. The low end from a transmission line system was awesome!" His review of the Fried Studio IV (Vol.8 No.4), a speaker with a smaller line-tunnel enclosure than the G/3, indicates deeper flat-bass extension than DO found for the G/3.

In addition, DO said about the G/3's upper mids: "There's a pervasive dry thin quality throughout the range that most notably affects string overtones." Again, this conflicts with JGH's observations on the sound at the SCES. DO also states that "Extreme treble is not sufficiently smooth and airy . . ." The G/3 and Studio IV share the same tweeter, crossed over at the same frequency, and to quote from JGH's review of the Studio IV, "Highs are positively gorgeous, open, smooth, and airy."

Without question, the G/3 review is "factitious," with the strengths of Fried speakers suddenly becoming weaknesses. The measurements on the bass must be corrected. The sad part about the appearance of this review is not only the damage it will inflict on the Fried Products company, but also on Stereophile. Attacks on people, conflicting statements, and flawed measurements will ruin your credibility and put your magazine alongside other lowly audio publications on the magazine racks.David E. Finley, Lower Burrell, PA

John Atkinson responds to Fried and Finlay, from January 1987 (Vol.10 No.1):

The trouble with measured defects, as far as someone who would attempt to deny a review's validity is concerned, is that no amount of rhetoric can reverse the measurement.

I too was surprised by the measured lack of low frequency extension of the G/3. Surprised enough, in fact, that I repeated Dick Olsher's measurements, using pink noise and a half-octave analyser, with the mike next to the woofer or port in Larry Archibald's very large room (see also the letter from Mr. Katz in this issue). It was this measurement that indicated the 31.5Hz band to be 9dB down compared with the level at 1kHz. (DO's more rigorous sinewave measurements showed that the response continued to drop below this band, shelving to 18dB at 20Hz.)

Mr. Fried informed me by phone that the response was indicative of a faulty sample with the woofer actually disconnected; as the results were identical for both speakers, however, and the woofers were visually and audibly not disconnected, a fault was ruled out. It might be that both speakers of the pair had somehow been assembled incorrectly; unfortunately for manufacturers, Stereophile's policy is to review products that appear to be working as received, and if units with a below-par performance have slipped through the manufacturer's quality control net, then we assume that that can happen to readers also.

In conversation with Mr. Fried, it emerged that he has ideas different from Stereophile about how the low-frequency cutoff of a loudspeaker should be measured. When assessing low-frequency extension, Mr. Fried measures the loudspeaker's response in-room, at the listening position. Unfortunately, this measurement includes the interaction between the speaker and the listening room at low frequencies. Not only will this interaction be unique to any given room and to any position in it; also, the room will boost the level of low bass by an arbitrary amount.

I prefer to get a more universally applicable, if less generous, figure by measuring the speaker's response under anechoic conditions. If an anechoic chamber is not availableand it hardly ever isthen measuring outdoors is a less-good substitute; at the least, taking the response in-room with the measuring microphone very close to the driver will still give a more accurate indication of the rolloff frequency than Mr. Fried's method.

Mr. Fried claimed that he measured the response of the G/3s to be flat to 25Hz in his room. He did not send us these measurements, but I would suggest that the above paragraph implies that this statement is not incompatible with Stereophile's nearfield measurements. Unfortunately for Mr. Fried, there are now speakers in existence, such as the KEF R107 and Thiel CS3.5, which do measure flat to below 25Hz under anechoic conditions, without the help of the room; subjectively, the G/3's extension has to be assessed against that of such speakers.

Regarding the disagreement between Dick Olsher and J.Gordon Holt about the G/3's mid and treble registers, the fact that JGH liked the quality of the Studio IV's high frequencies is neither here nor there, despite the use of the same tweeter. Differences in the midrange unit, the crossover design, and in the voicing of the speaker's tonal balance can bring about the differences noted.

In addition, as mentioned in the review, it turned out that the G/3 as submitted was not a finished product; a major revision to the crossover network was performed late in the review period to make the speakers conform to Fried's current production. It could well be that the G/3s heard by JGH at CES were different again.

Finally, regarding Fried's "line-tunnel" nomenclature, we have to disagree with Mr. Finley. There are three fundamental ways other than horn-loading in which a dynamic drive-unit can be mounted in an enclosure: the "infinite baffle" or sealed box; the transmission line; and the ported or "reflex" enclosure (which includes such variations as the KEF coupled cavity). The first two attempt to prevent the backwavethe out-of-phase radiation from the rear of the conefrom reaching the outside world and interfering with the sound from the front; the thirdthe reflexadds the backwave radiation to that from the front of the cone, in-phase at frequencies above the resonance of the port, and out-of-phase below.

The G/3, just as DO described it, is a reflex, having a ported enclosure. Bud Fried has pointed out that the port is not tuned in traditional reflex manner, and has additional damping in the form of foam in the port and in the cabinet, and that it therefore should be regarded as a new form of loading. With respect, I disagree. It is an overdamped reflex design and I regard Mr. Fried's "line-tunnel" nomenclature as confusing: it implies some form of transmission line loading, as JGH indicated in the Summer 1986 CES report to which Mr. Finley refers. And a 6dB/octave rolloff? I am at a loss to know where Mr. Finley obtains this figure as even the most gentle casea sealed-box speakerwill roll off at 12dB/octave below its resonance.

With hindsight, I can see that Stereophile shouldn't have reviewed the Fried G/3 so soon after its commercial introduction; rather, we should have waited for the design to settle down to its final form.John Atkinson